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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

Náhrada parovodu horkovodem v systému centrálního zásobování teplem teplárny Martinská teplárenská, a.s / Substitution of steam by hot water in heat distribution net

Mužila, Martin January 2014 (has links)
The work is focused on area of exchanging steam distribution net for hot water one, in central distribution net of Martin’s heating plant. The main subject, which talks about pros and cons in this exchange process, is determination of heat losses which are created on heat distribution net during different operating status. These heat losses are calculated and on their basis some conclusions are concluded. Moreover, new heat exchanger is designed for certain conditions and also mathematical model of distribution net is created, which is suitable for checking different operating status. As a result of the work is technic’s and economic’s analysis of this project.
472

Pružné spojky na principu tekutin / Flexible couplings on the principle of fluid

Machů, Tomáš January 2014 (has links)
The thesis deals with flexible shaft couplings especially with new category of flexible couplings on the principle of fluid. Mathematical model of gas spring and rotor system with two degrees of freedom are derivated in this work. Last part of the work deals with design modification of flexible coupling with gas springs.
473

Vliv provozních parametrů spalování a konstrukčních parametrů nízkoemisního hořáku na charakteristické parametry spalovacích procesů / The influence of operating parameters and construction parameters of the low-NOx burner on characteristic parameters of combustion processes

Nykodým, Jiří January 2015 (has links)
The main aim of the work was the investigation of the effect of operational parameters of the combustion process (combustion air excess, primary fuel ratio) and burner constructional parameters (the pitch angle of secondary nozzles, tangential orientation of secondary nozzles towards the axis of the burner) on the formation of NOx and CO, flue gas temperature, the shape, dimensions and stability of the flame, in-flame temperatures in the horizontal symmetry plane of the combustion chamber and the amount of heat extracted from the hot combustion gases in the combustion chamber’s shell. Experimental activities were carried out in the laboratory of the Institute of Process and Environmental Engineering, which is focused on burners testing. The combustion tests were performed with the experimental low-NOx type burner, namely the two-gas-staged burner. Mathematical model developed based on the experimental data describes the dependency of NOx on the operating parameters of the combustion process and burner constructional parameters. The model shows that increasing air excess and increasing angle of tangential orientation of the secondary nozzles reduce the formation of NOx. The temperature peaks in the horizontal symmetry plane of the combustion chamber decreases with increasing combustion air excess. The thermal load to the combustion chamber’s wall along the length of the flame was evaluated for selected settings. It was validated that the thermal efficiency of is reduced when higher air excess is used.
474

Metoda konečných prvků v časové oblasti a její aplikace / Finite Element Time Domain and Its Applications

Cigánek, Jan January 2014 (has links)
Disertační práce se zabývá modelováním dispersních materiálů metodou konečných prvků v časové oblasti. V práci jsem navrhl matematický model zahrnující dispersní modely a aplikoval jsem na něj metodu konečných prvků. Pozornost jsem věnoval třem nejvíce používaným dispersním modelům. Jedná se o Debyeho model, Lorentzův model a Drudův model. Dále jsem se zabýval technikami implementace těchto dispersních modelů. Techniky jsem zabudoval do metody konečných prvků. Navíc jsem vyvinul novou metodu založenou na technice digitální filtrace. Funkčnost vyvinutých metod a technik jsem ověřil na řadě testovacích příkladů. Diskutoval jsem dosažené výsledky a navrhuji jejich možná vylepšení.
475

Hybridní řídicí systém pro quadrokoptéru / Hybrid Control System for Quadrocopter

Sojka, Stanislav January 2013 (has links)
This thesis deals with the design and theoretical description of the hybrid control system for quadrocopter. First, a mathematical model is presented, sensors needed for development and their principles. This work shows the system architecture design and scheme of communication channels between the blocks. Implementation section discusses specific uses of computing nodes/sensors and their settings. In this thesis there are illustrated messages sent between computing nodes and the control loop machine. It also describes how to test the sensors, measurement results and techniques for improvement.
476

Experimentální a numerická analýza zesílení ŽB prvku na smykové účinky / Experimental and numerical analysis of reinforced concrete reinforcement member subjected to shear forces

Folvarčná, Ingrid January 2016 (has links)
Design and manufacture of test elements for experimental laboratory testing of shear damage. Testing of selected mechanical characteristics of test elements. Experimental analysis of test elements in the lab, creating a mathematical model in ATENA software, static analysis. Evaluation of experimental analysis and comparison with the values of static analysis. Final overall evaluation.
477

Kmitání stlačitelné tekutiny ve válcové oblasti / Oscillation of the compressible fluid in the cylindrical space

Smolík, Adam January 2016 (has links)
The thesis includes two main parts. The first part comprises the theoretical analysis, i.e. literary research. It has been focused on questions regarding compressive pulsation and possible damping elements. The second part focuses on the formation of mathematical model of transition of matrix gas accumulator, the hydraulic set formation by the transition matrix method, the deduction of innate and constrained values and the compressible liquid mode shapes in cylindrical space.
478

Srovnání optimalizačních metod pro odhad perfúzních parametrů / Comparison of optimization methods for perfusion parameters estimation

Kříž, Marek January 2016 (has links)
The content of this thesis is to understand the principle of ultrasound imaging and mathematical models used to estimate perfusion parameters of concentration curves. Thesis deals with global optimization algorithms for finding parameters, an approximation of the actual data model curves. It also includes a comparison of different methods and used functions.
479

Modely a metody pro svozové úlohy / Models and methods for routing problems

Nevrlý, Vlastimír January 2016 (has links)
This master's thesis deals with mathematical model building for routing problems and ways to solve them. There are discussed and implemented deterministic and heuristic approaches that are suitable to be utilized. A big effort is put into building of the mathematical model describing a real world problem from the field of waste management. Appropriate algorithms are developed and modified to solve a particular problem effectively. An original graphical environment is created to illustrate acquired results and perform testing computations.
480

Numerické modelování proudění v bezpečnostním objektu vodního díla / Numerical Modelling of Flow over Spillway

Holinka, Matouš January 2017 (has links)
This thesis deals with the solution of numerical modeling. Consequently problems associated with the flow of the water over spillway of the specific water structure. In this case numerical modeling means modeling of fluid movement, which is described by mathematical means. Especially nowadays, when a lot of spillways need to be recalculated, whether it meets the capacity demands, or there is no need to tackle reconstruction. With today's software capabilities there is a wide range of commercial and freeware resources. The numerical model, compared to physical model is less accurate which is, on the otherhand, physical model is usually financially and time-consuming. The following work simulates the behavior of water on the edge of the spillway, in the trough and then behind the trough. The result is a comparison of the water depth in the trough calculated by the numerical and the physical model.

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